Support/fix for star-tree keyword aggregation dfs mode

[sandeshkr419]

Description

TLDR: DFS flow in keyword terms was returing empty buckets, this PR fixes the flow for DFS case.

Detailed Explanation of Changes:
The existing strategy where we fetch which bucketOrd to update:

long bucketOrd = collectionStrategy.globalOrdToBucketOrd(0, ord);

For DenseGlobalOrds (used by breadth-first flow) implementation: would return the bucket in for correctly

 @Override
        long globalOrdToBucketOrd(long owningBucketOrd, long globalOrd) {
            assert owningBucketOrd == 0;
            return globalOrd;
        }
        

For RemapGlobalOrds (used by depth-first flow) implementation: was returning -1 when it was trying to find a bucket, and hence bucket was not getting initialized properly with correct values.

@Override
        long globalOrdToBucketOrd(long owningBucketOrd, long globalOrd) {
            return bucketOrds.find(owningBucketOrd, globalOrd);
        }

We needed a new utility to find or create bucket if not available so I have introduced a new utility to resolve the same:

 abstract long getOrAddBucketOrd(long owningBucketOrd, long globalOrd) throws IOException;

This change ensures that both the cases. bfs/dfs are handled correctly.

Added test cases to handle the same.

Related Issues

Resolves #[Issue number to be closed when this PR is merged]

Check List

• Functionality includes testing.
• API changes companion pull request created, if applicable.
• Public documentation issue/PR created, if applicable.

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[github-actions]

✅ Gradle check result for d4f6597: SUCCESS

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 72.58%. Comparing base (631bed4) to head (d4f6597).
Report is 21 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main   #18354      +/-   ##
============================================
+ Coverage     72.53%   72.58%   +0.05%     
- Complexity    67396    67439      +43     
============================================
  Files          5492     5492              
  Lines        311127   311128       +1     
  Branches      45224    45223       -1     
============================================
+ Hits         225680   225846     +166     
+ Misses        67063    66868     -195     
- Partials      18384    18414      +30     

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[sandeshkr419]

This was some dead code which I removed. Not related to the PR.

[github-actions]

❌ Gradle check result for cd9c5be:

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?